Added GetKnownFolderPath

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@7154 212acab6-be3b-0410-9dea-997c60f758d6

Docs/src/generalpurpose.but

@@ -81,6 +81,17 @@ Gets the last write time of "filename". Sets the user output variables with the
 
 This is similar to \R{getfiletime}{GetFileTime}, only it acts on the system building the installer (it actually compiles into two \R{StrCpy}{StrCpy} commands). Sets the two output variables with the file timestamp of the file on the build system.
 
+\S2{getknownfolderpath} GetKnownFolderPath
+
+\c user_var(output) knownfolderid
+
+Get the path of a \W{https://docs.microsoft.com/en-us/windows/win32/shell/knownfolderid}{known folder}. The error flag is set and the output variable is empty if the call fails or the knownfolderid guid is not available. This function is only able to resolve known folders Windows Vista or higher.
+
+\c !include WinCore.nsh
+\c GetKnownFolderPath $InstDir ${FOLDERID_UserProgramFiles}
+\c StrCmp $InstDir "" 0 +2 
+\c StrCpy $InstDir "$LocalAppData\Programs"
+
 \S2{getfullpathname} GetFullPathName
 
 \c [/SHORT] user_var(output) path_or_file

Docs/src/history.but

@@ -12,6 +12,8 @@ Released on ? ?th, 2020
 
 \S2{} Major Changes
 
+\b Added \R{getknownfolderpath}{GetKnownFolderPath}
+
 \S2{} Minor Changes
 
 \b Added \R{ifshellvarcontextall}{IfShellVarContextAll} and \R{ifrtllanguage}{IfRtlLanguage}